A liquid crystal display is a device that has a display portion including a plurality of pixels arranged therein and a flame portion around the display portion, and displays an image on the display portion utilizing electrooptic properties of liquid crystal molecules. Such liquid crystal displays are widely used for various devices such as mobile phones, laptops, and liquid crystal TVs. As such a liquid crystal display, an active matrix-driving liquid crystal display is well-known. A liquid crystal display of this type has an active matrix substrate (hereafter, also referred to as an array substrate). The array substrate commonly has wiring such as bus lines and lead wires connected to the bus lines, pixel electrodes, and switching elements such as thin film transistors (TFTs). As the bus lines, commonly, source bus lines and gate bus lines are provided.
Recently, liquid crystal displays have been required to have a higher-resolution screen in applications such as smartphones and tablet PCs, leading to narrower pitches between bus lines (e.g., source bus lines). In addition, display with a wider viewing angle has been also demanded.
Known examples of typical liquid crystal modes satisfying such demands include: the vertical alignment (VA) mode in which the alignment of liquid crystal molecules having negative dielectric anisotropy is controlled by application of an electric field in the direction orthogonal to the substrate surface; and the horizontal alignment mode in which the alignment of liquid crystal molecules having positive or negative dielectric anisotropy is controlled by application of an electric field (transverse electric field) in the horizontal direction (parallel direction) relative to the substrate surface. Moreover, a proposed liquid crystal display of the horizontal alignment mode is a liquid crystal display of the fringe field switching (FFS) type. A FFS liquid crystal display performs display by application of a fringe electric field (oblique electric field including the transverse electric field and vertical electric field) to a liquid crystal layer.
A disclosed FFS liquid crystal display is a FFS liquid crystal display in which a pixel electrode and a common electrode are positioned on a planarizing film so that plural contact holes can be formed at once in a single step (see Patent Literature 1).
Also disclosed is a FFS liquid crystal display capable of satisfactorily securing supply of a common potential to a common electrode and enhancing the aperture ratio of pixels to obtain bright display (see Patent Literature 2).
Also disclosed is a FFS liquid crystal panel in which the resistance value of a common electrode having a slit-like opening is decreased to reduce flicker and crosstalk (see Patent Literature 3).